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Question 1 · Free response · 中档
(5 分)已知集合 $A = \{ x \vert 2 < x < 4 \}$ $B = \{ { \bf x } | { \bf x } < 3$ 或 $x > 5 \}$ ,则A∩B=( )A $\{ \times | 2 < x < 5 \}$ B $\{ \times \vert \times < 4$ 或 $x > 5 \}$ C $\{ \mathbf { \mu } _ { \mathbf { X } } | 2 < \mathbf { \mu } _ { \mathbf { X } } < 3 \}$ D. $\{ \times \vert \times < 2$ 或 $_ { \times > 5 } \}$
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Question 3 · Single choice · 中档
(5分)执行如图所示的程序框图,输出s的值为( )
A. 8 B. 9 C. 27 D. 36
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Question 4 · Single choice · 中档
(5 分)下列函数中,在区间(-1,1)上为减函数的是( )
A. $y=\frac{1}{1-x}$ B. $y=\cos x$ C. $y=\ln (x+1)$ D. $y=2^{-x}$
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Question 5 · Free response · 中档
(5分)圆 $( x + 1 ) 2 + y ^ { 2 } = 2$ 的圆心到直线y=x+3的距离为( )A.1 B.2 C $\sqrt { 2 }$ D $2 \sqrt { 2 }$
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Question 6 · Free response · 中档
(5分)从甲、乙等5名学生中随机选出2人,则甲被选中的概率为( )
A $\frac { 1 } { 5 }$ B $\frac { 2 } { 5 }$ C $\frac { 8 } { 2 5 }$ D $\frac { 9 } { 2 5 }$
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Question 7 · Single choice · 中档
(5 分)已知 A(2,5),B(4,1).若点 P(x,y)在线段 AB 上,则 $2 x - y$ 的最大值为( )
A. ﹣1 B. 3 C. 7 D. 8
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Question 8 · Free response · 中档
(5 分)某学校运动会的立定跳远和 30 秒跳绳两个单项比赛分成预赛和决赛两个阶段,表中为10名学生的预赛成绩,其中有三个数据模糊
<table><tr><td rowspan=1 colspan=1>学生序号</td><td rowspan=1 colspan=1>1</td><td rowspan=1 colspan=1>2</td><td rowspan=1 colspan=1>3</td><td rowspan=1 colspan=1>4</td><td rowspan=1 colspan=1>5</td><td rowspan=1 colspan=1>6</td><td rowspan=1 colspan=1>7</td><td rowspan=1 colspan=1>8</td><td rowspan=1 colspan=1>9</td><td rowspan=1 colspan=1>10</td></tr><tr><td rowspan=1 colspan=1>立定跳远(单位:米)</td><td rowspan=1 colspan=1>1.96</td><td rowspan=1 colspan=1>1.92</td><td rowspan=1 colspan=1>1.82</td><td rowspan=1 colspan=1>1.80</td><td rowspan=1 colspan=1>1.78</td><td rowspan=1 colspan=1>1.76</td><td rowspan=1 colspan=1>1.74</td><td rowspan=1 colspan=1>1.72</td><td rowspan=1 colspan=1>1.68</td><td rowspan=1 colspan=1>1.60</td></tr><tr><td rowspan=1 colspan=1>30 秒跳绳(单位:次)</td><td rowspan=1 colspan=1>63</td><td rowspan=1 colspan=1>a</td><td rowspan=1 colspan=1>75</td><td rowspan=1 colspan=1>60</td><td rowspan=1 colspan=1>63</td><td rowspan=1 colspan=1>72</td><td rowspan=1 colspan=1>70</td><td rowspan=1 colspan=1>a - 1</td><td rowspan=1 colspan=1>b</td><td rowspan=1 colspan=1>65</td></tr></table>
在这10名学生中,进入立定跳远决赛的有8人,同时进入立定跳远决赛和 30秒跳绳决赛的有6人,则( )A.2号学生进入30秒跳绳决赛 B.5号学生进入30秒跳绳决赛C.8号学生进入30秒跳绳决赛 D.9号学生进入30秒跳绳决赛
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Question 10 · Free response · 中档
(5分)函数 $f ( x ) = \frac { x } { x - 1 } ( x \geq 2 )$ 的最大值为 2
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Question 11 · Free response · 中档
(5分)某四棱柱的三视图如图所示,则该四棱柱的体积为 $- \frac { 3 } { 2 } -$ -
正(主)视图
侧(左)视图
俯视图
Answer key $\frac { 3 } { 2 }$
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Question 12 · Free response · 中档
(5 分)已知双曲线 $\frac { \texttt { x } ^ { 2 } } { \texttt { a } ^ { 2 } } - \frac { \texttt { y } ^ { 2 } } { \texttt { b } ^ { 2 } } = 1 ( { \texttt { a } } > 0 , { \texttt { b } } > 0 )$ )的一条渐近线为 $2 x + y = 0$ 个焦点为 $( \sqrt { 5 } , \ 0 )$ ),则 $a = \_ 1 , b = \_ 2$
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Question 13 · Free response · 中档
(5 分)在 $\triangle A B C$ 中, $\angle A = \frac { 2 \pi } { 3 } , \mathsf { a } = \sqrt { 3 } \mathsf { c }$ ,则 $\frac { b } { c } = \frac { 1 } { 1 }$
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Question 14 · Free response · 中档
(5分)某网店统计了连续三天售出商品的种类情况:第一天售出19种商品,第二天售出13种商品,第三天售出18种商品;前两天都售出的商品有 3种,后两天都售出的商品有4种,则该网店
①第一天售出但第二天未售出的商品有 16 种;
②这三天售出的商品最少有 29 种
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Question 15 · Free response · 中档
(13 分)已知 $\{a_n\}$ 是等差数列,$\{b_n\}$ 是等比数列,且 $b_2=3$,$b_3=9$,$a_1=b_1$,$a_{14}=b_4$. (1)求 $\{a_n\}$ 的通项公式; (2)设 $c_n=a_n+b_n$,求数列 $\{c_n\}$ 的前 $n$ 项和.
Answer key ① $a_n=2n-1$;② $S_n=n^2+\dfrac{3^n-1}{2}$
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Question 16 · Free response · 中档
已知函数 $f(x)=2\sin\omega x\cos\omega x+\cos2\omega x$($\omega>0$)的最小正周期为 $\pi$. (1)求 $\omega$ 的值; (2)求 $f(x)$ 的单调递增区间.
Answer key (1)$\omega=1$;(2)$\left[-\frac{3\pi}{8}+k\pi,\ \frac{\pi}{8}+k\pi\right]$($k\in\mathbb{Z}$)
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Question 17 · Free response · 中档
(13分)某市居民用水拟实行阶梯水价,每人月用水量中不超过w立方米的部分按4元/立方米收费,超出w立方米的部分按10元/立方米收费,从该市随机调查了 10000 位居民,获得了他们某月的用水量数据,整理得到如图频率分布直方图:
(1)如果w为整数,那么根据此次调查,为使80%以上居民在该月的用水价格为4元/立方米,w至少定为多少?
(2)假设同组中的每个数据用该组区间的右端点值代替,当$w=3$时,估计该市居民该月的人均水费
Answer key (1) 3立方米; (2) 10.5元
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Question 18 · Free response · 中档
(14 分)如图,在四棱锥 P﹣ABCD 中,PC⊥平面 ABCD,AB∥DC,DC⊥AC
(1)求证:DC⊥平面PAC;(2)求证:平面PAB⊥平面PAC;
(3)设点E为AB的中点,在棱PB上是否存在点F,使得PA∥平面CEF?说明理由.
Answer key See explanation
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